by Stewart MasonAlthough not as well known as Drumming or Music for 18 Musicians, 1981's Tehillim has earned its place next to those works in Steve Reich's canon. It's arguably his most mature and fully realized work, taking the various strands which had intrigued him before (including African percussion, the human voice, and the power of subtly changing patterns) and developing them in new and interesting ways. The title is Hebrew for "Psalms," and the chants the female vocals develop throughout are indeed liturgical texts. As such, they have a rhythm of their own which plays off of the steady pulse of the finger cymbals in interesting ways, placing accents in unexpected places. Meanwhile, Reich -- for the first time in his mature career as a composer -- experiments with modulation between keys and other elements of tonality that he had previously ignored. Indeed, when the final movement, after three movements' worth of Reich's characteristic tonal ambiguity, finally "affirms the key of D major as the basic tonal center," as Reich's lucid liner notes helpfully explain, the effect, combined with the increasing power and passion of the female voices, is astonishing.